1. Field of the Invention
The present invention relates to portable gangways, stairways, ladders and the like. More particularly, the present invention relates to a portable gangway having a series of steps and means for maintaining the steps horizontal and level as an angle of inclination of the gangway is varied.
2. Description of the Related Art
The need to walk or travel from one floor, platform level, or deck to another is encountered by most people throughout the course of their daily excursions. When two or more levels are fixed as a permanent structure and do not move relative to one another, a fixed structure such as a stairway, escalator and/or elevator are often employed as a means to facilitate convenient and safe passage between the two or more levels. In other instances, the various levels may be mobile or transitory, and thus a fixed structure is not practical. Still, in other situations, two platform levels or deck surfaces may constantly move relative to one another. A boat rising and lowering with the tide relative to a dock is an example of this type of a situation. In these instances, wherein a fixed structure such as a stairway is not practical, ladders, planks, ramps, and remote gangways are typically used so that persons can walk or climb from one deck surface level to another.
In the past, ladders, gangways, and ramps have proven to be awkward, especially when at least one of the deck surfaces is moving. Many times, the angle of inclination of a ramp or ladder make it dangerous, if not impossible, to traverse between two deck surfaces or platforms. For instance, when the angle of inclination of a ladder becomes more horizontal, the top step surfaces become awkwardly angled, requiring a person to step on the edge of the step, rather than the top surface. On the other hand, a ramp becomes too difficult to travel when it reaches angles of inclination of 40.degree. of greater, becoming more vertically inclined.
In an effort to accommodate for varying heights and distances between two platform or deck surfaces, various adjusting stairways, gangways, and ladders have been proposed in the related art. Many of these proposed structures are cumbersome, heavy and not easily transported for use at various locations. Further, some of these proposed adjusting and/or portable ladders have been known to collapse while people are traversing or transporting them causing serious injury. The proposed structures in the prior art all fail to provide a convenient, safe, portable and lightweight yet sturdy gangway having a series of steps which continually adjust so that a top flat step surface of each of the steps remains level as the angle of inclination of the gangway changes while also providing means to protect the user from moving parts that sometimes cause injury.